Best books/resources to learn the Black side of the QGD?

chessable.com

Objectively speaking, QGD: Baltic defense 2...Bf5?! looks like an inaccuracy. 

Sadler's Queens Gambit Declined has a lot of explanations.

Watson's Mastering the Chess Openings volume 2 has good explanations too.

Sadler's book is amongst the best written for concepts in the QGD.  Don't take the theory as gospel though as it is 18 years old.

John Cox's "Declining the Queen's Gambit" is also an excellent book, but it's not objective like the Sadler book is.  It is more of a repertoire, covering both the Tartakower and the Lasker Variations against the main lines.  Then of course, it also covers the Exchange, Bf4 lines, and the Catalan.

Sadler's books are great, but in my view the best one is Drazen Marovic's 'Play the Queen's Gambit'. It's a few years older than Sadler's, but it doesn't really matter. You'll learn how to play the Queen's Gambit.

hicetnunc wrote: "Sadler's Queens Gambit Declined ..."

https://web.archive.org/web/20140708234438/http://www.chesscafe.com/text/hansen15.txt

hicetnunc wrote: "... Watson's Mastering the Chess Openings volume 2 ..."

http://dev.jeremysilman.com/shop/pc/Mastering-the-Chess-Openings-Volume-2-76p3570.htm

http://www.gambitbooks.com/pdfs/Mastering_the_Chess_Openings_volume_2.pdf

https://web.archive.org/web/20140627115737/http://www.chesscafe.com/text/hansen99.pdf

ThrillerFan wrote: "... John Cox's 'Declining the Queen's Gambit' ..."

https://web.archive.org/web/20140626233841/http://www.chesscafe.com/text/hansen149.pdf

"Though extremely White-biased, [Play the Queen's Gambit by Drazen Marovic (1992)] is a classic and should probably be on the shelf of anyone who takes on the Queen's Gambit from either side."

http://www.kenilworthchessclub.org/games/java/2007/lasker-kenilworth-repertoire.htm

Black Side of the QGD = Dark Side of the Force ?!? 

Two recent introductory opening books:

First Steps: The Queen's Gambit

https://www.newinchess.com/media/wysiwyg/product_pdf/7652.pdf

The Queen's Gambit Declined: Move by Move.

https://www.newinchess.com/media/wysiwyg/product_pdf/7743.pdf

As mentioned, Queen's Gambit Declined  by Matthew Sadler is a very instructive introduction to the fundamentals of the QGD (it won the Book of the Year award in 2000 from the British Chess Federation).  Also check out "First Steps: The Queen's Gambit" by Andrew Martin; "Starting Out: Queen's Gambit Declined" by Neil McDonald; "Starting Out: 1 d4!" by John Cox; "Declining the Queen's Gambit" by John Cox; “Chess Explained: Queen’s Gambit Declined” by James Rizzitano: and "How To Beat 1.d4", by James Rizzitano, which covers the Queen's Gambit ACCEPTED.

I think the Tartakower Variation of QGD for Black would be a good one to learn...

This is a pretty good introduction video summary to the QG (Tartakower V. at minute 11:20)...

https://www.youtube.com/watch?v=7XuDDQ4S5Sg

https://web.archive.org/web/20140627005627/http://www.chesscafe.com/text/hansen93.pdf

"... Cox's book suggests a complete repertoire for White beginning with 1 d4. …"

http://theweekinchess.com/john-watson-reviews/the-end-of-openings-part-1

https://web.archive.org/web/20140627032909/http://www.chesscafe.com/text/hansen89.pdf

https://web.archive.org/web/20140626234756/http://www.chesscafe.com/text/hansen104.pdf

https://web.archive.org/web/20140626201436/http://www.chesscafe.com/text/hansen80.pdf

Thanks everyone, Sadler wins! ... Is there a particular title that would make a good follow-up and another that may be considered a good reference? 

I have quite a few of the books mentioned above. 

The key isn't to choose the right book, as there are several good choices. The key is to actually study the book thoroughly. Go through the main lines first and really understand Black's goals and thematic plans. 

Buying  a book is easy. Getting the most out of it will require a real commitment.

@dannyhume -

While it is certainly true that if you are going to purchase a book, the only way to benefit from it is to make use of it (which normally implies a commitment to studying it), it is also true that some books are better suited to addressing the reader's objectives than others, depending, of course, upon whether one is primarily interested in an introductory treatment, a repertoire, a comprehensive theoretical presentation, a reference work, etc.

As well, the issue of "better" is obviously a subjective and personal one; so with that caveat, I will offer what I consider to be several of the better titles, from the perspective of learning to play the QGD:

1. Matthew Sadler's "Queen's Gambit Declined" - an excellent, instructive and award winning introduction to the QGD (and pronounced the winner by the OP).  Focuses on themes, plans, goals etc.

2. "Starting Out: The Queen's Gambit Declined" by Neil McDonald.  Another very instructive introduction to, and overview of the QGD in the vein of the Sadler book.  This would be a good supplement for learning the themes, plans, strategies etc.

3. "Declining the Queen's Gambit" by John Cox.  A repertoire and "reference" book for Black.  The Tartakower Variation is the featured variation, with the Lasker Variation as an alternative.  Also covered are the Exchange Variation, the Bf4 Variation, the Catalan, and alternative lines where White attempts to avoid these variations.  Understand that this is not an introductory treatment, but instead is more of a follow-on to the Sadler and McDonald books.  As such it is less concerned with explication of themes and plans, and more concerned with a reasonably comprehensive presentation of the theory, i.e., lines of play, consistent with the repertoire.

These books will do a good job of getting you started playing the QGD.

http://dev.jeremysilman.com/shop/pc/My-Best-Games-of-Chess-1908-1937-p3793.htm

https://chessbookreviews.wordpress.com/tag/alekhines-best-games/

https://static1.squarespace.com/static/5856bd64ff7c50433c3803db/t/5a5296bcc830256b61a7b94d/1515361980898/mbgexerpt.pdf